Open AccessFas and Fas ligand expression in the salivary glands of patients with primary Sjögren's syndrome
Author(s) -
Kong Liping,
Ogawa Noriyoshi,
Nakabayashi Toru,
Liu George T.,
D'Souza Errol,
McGuff H. Stan,
Guerrero Daniel,
Talal Norman,
Dang Howard
Publication year - 1997
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.1780400113
Subject(s) - fas ligand , apoptosis , programmed cell death , dna fragmentation , fas receptor , biology , pathology , salivary gland , immunohistochemistry , microbiology and biotechnology , immunology , medicine , biochemistry
Objective . To assess the role of Fas ‐mediated apoptosis in the salivary glands of patients with primary Sjögren's syndrome (SS). Methods . Expression of Fas, Fas ligand ( Fas L), and bcl ‐2 in salivary gland biopsy material was detected in situ by immunohistochemical staining and reverse transcriptase‐polymerase chain reaction. DNA fragmentation in apoptotic cells was assessed by the enzymatic incorporation of labeled nucleotides (digoxigenin‐dUTP). Results . The acinar epithelial cells in SS were Fas + and Fas L+, and these cells died by apoptosis. The majority of infiltrating lymphocytes in SS were Fas + and bcl‐2+, while few lymphocytes expressed Fas L. In situ detection of apoptosis showed minimal cell death of lymphocytes, particularly in dense periductal foci. Lymphocytic cell death was significantly lower ( P < 0.0001) in these foci compared with that in the interstitium. Conclusion . Infiltrating lymphocytes in the focal lesions of the salivary glands of patients with SS are blocked in their ability to commit to apoptosis, even though they may express Fas . The presence of bcl ‐2 in these cells may explain their inability to undergo apoptosis. The acinar epithelial cells, in contrast, may undergo Fas ‐mediated apoptosis. These results suggest that the Fas death pathway may be an important mechanism leading to the glandular destruction found in SS.